Top Stories - Posted by Jacob Levich-Stony Brook on Wednesday, August 29, 2012 11:31 - 0 Comments
Penguins grow ‘frigid’ as Antarctic warms up
STONY BROOK (US) — As temperatures rise on the Antarctic Peninsula, the number of breeding chinstrap penguins is down by more than half, new research shows.
Published in the Polar Biology, the findings stem from fieldwork conducted in December 2011 at Deception Island, one of the most frequently visited locations in Antarctica. There has been speculation that tourism may have a negative impact on breeding chinstrap penguins—especially, at Baily Head, the penguins’ largest colony.
Previously, Antarctic Treaty-level discussions regarding the management of visitors at Baily Head proceeded in the absence of concrete site-wide census data.
Straight from the Source
Overseen by Ron Naveen, founder of the nonprofit science and conservation organization, Oceanites, Inc., the Deception Island census effort analyses were undertaken by Heather Lynch, assistant professor of ecology and evolution at Stony Brook University, and chief scientist of the Antarctic Site Inventory project.
The Inventory has been collecting and analyzing Antarctic Peninsula-wide penguin population data since 1994, and the new findings have important implications both for the advancement of Antarctic science and the management of Antarctica by the Antarctic Treaty nations.
“Our Deception Island work, using the yacht Pelagic as our base, occurred over 12 days and in the harshest of conditions—persistent clouds, precipitation, and high winds, the latter sometimes reaching gale force and requiring a lot of patience waiting out the blows,” Naveen says.
“But, in the end, we achieved the first-ever survey of all chinstraps breeding on the island.”
The results and analyses shed new light on the massive changes occurring in this region.
“Our team found 79,849 breeding pairs of chinstrap penguins at Deception, including 50,408 breeding pairs at Baily Head, Lynch says.
“Combined with a simulation designed to capture uncertainty in an earlier population estimate, there is strong evidence to suggest a significant (greater than 50 percent) decline in the abundance of chinstraps breeding at Baily Head since 1986/87.
“The decline of chinstrap penguins at Baily Head is consistent with declines in this species throughout the region, including at sites that receive little or no tourism; further, as a consequence of regional environmental changes that currently represent the dominant influence on penguin dynamics, we cannot ascribe any direct link in this study between chinstrap declines and tourism.”
Lynch and colleagues analyzed high-resolution satellite imagery from the 2002/03 and the 2009/10 seasons that suggest a 39 percent decline over that seven-year period, and which provide independent confirmation of this population decline.
With assistance from the US National Science Foundation and the University of Minnesota’s Polar Geospatial Center, the Inventory continues to demonstrate the use of satellite imagery to analyze and describe environmental change in sensitive habitats.
“We now know that two of the three predominant penguin species in the Peninsula—chinstrap and Adélie—are declining significantly in a region where, in the last 60 years, it’s warmed by 3˚ C. (5˚ F.) annually and by 5˚ C. (9˚ F.) in winter,” Naveen says.
“By contrast, gentoo penguins, the third of these species, are expanding both its numbers and range. These divergent responses are an ongoing focus of our Inventory work effort.”
“While there has been considerable focus in the policy and management community about the potential impact of tourism on these penguin populations, we cannot forget the overwhelming evidence that climate is responsible for the dramatic changes that we are seeing on the Peninsula,” Lynch says.
“If tourism is having a negative impact on these populations, it’s too small an effect to be detected against the background of climate change.”
The research is supported by the US National Science Foundation and public contributions, and the project’s on-the-ground fieldwork at Deception Island was specifically supported by a grant from The Tinker Foundation.
The Inventory is the only publicly supported science project working in Antarctica and the only science project tracking penguin populations throughout the entire Antarctic Peninsula region.
Antarctic Site Inventory researcher Steven Forrest counts penguins at Baily Head, Deception Island. (Credit: Photography ©2012 by Thomas Mueller)
Source: Stony Brook University